The invention relates to a measuring device and method for determining the amounts of gas and liquid in a fluid by a variation of volume in a positive-displacement pump as well possibly as physical characteristics or values of these characteristics of the fluid subjected to this variation of volume.
The invention applies in particular to the production of hydrocarbons comprising a multi-phase gas-liquid mixture, such production being carried out in particular, but not exclusively, in an environment which is difficult of access, for example at the level of an underwater well head or transfer line, or else in the virgin forest.
The invention also applies to the chemical or petroleum industry or generally to all industries using multi-phase fluids.
The invention applies advantageously to the transfer of multi-phase fluids, particularly when such transfer is effected by means of a positive-displacement pump.
Physical measurements of a fluid comprising a liquid phase and a gas phase are made for determining the relative amount of each phase. However, such measurements are made from a sample which is generally not representative of the fluid. These measurements are made in the laboratory which requires a certain delay before the results are available. These measurements are obtained, for example, during distillations, from pressure or temperature variations.
By GLR, or value of the parameter GLR, is meant the value of the ratio of the volume of gas to the volume of liquid in a fluid, this ratio being given under fixed pressure and temperature conditions.
A characteristic value is the number which quantifies one of the characteristics of a physical phenomenon. The assembly of characteristics mathematically translates all the possible configurations of a phenomenon.
To overcome the drawbacks of the above mentioned prior techniques, the present invention provides a method and device for obtaining in particular the GLR.